document.write( "Question 454678: it took a motorboat 2 h more to travel 32 mi against a current than it took to travel 32 mi with the current. the rate of the current was 4 mph. find the rate of the boat in calm water \n" ); document.write( "
Algebra.Com's Answer #312165 by mananth(16946)\"\" \"About 
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spee with wind x+4 mph
\n" ); document.write( "speed against wind=x-4 mph
\n" ); document.write( "Total flying time = 5.33 hours
\n" ); document.write( "Time with wind= -32/(x+4 )
\n" ); document.write( "time against wind 32/(x-4)
\n" ); document.write( "time against wind - time with wind = 2
\n" ); document.write( "-32/(x+4)+32/(x -4)=2
\n" ); document.write( "LCD =(x+ 4)*(x-4)
\n" ); document.write( "multiply the equation by the LCD
\n" ); document.write( "we get
\n" ); document.write( "-32*(x-4 )+32(x+4)=2(x^2-16)
\n" ); document.write( "-32x128+ 32x+128 )=2X^2-32
\n" ); document.write( "0x+256=2 x^2-32
\n" ); document.write( "2x^2-256 -32=0
\n" ); document.write( "2x^2-288 =0
\n" ); document.write( "/2
\n" ); document.write( "X^2-144 =0
\n" ); document.write( "x^2=144
\n" ); document.write( "x= +/- 12\r
\n" ); document.write( "\n" ); document.write( "x = 12 mph the boat speed
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